[debug] remove StepFrame

src/runtime/runtime-debug.cc

Index: src/runtime/runtime-debug.cc
diff --git a/src/runtime/runtime-debug.cc b/src/runtime/runtime-debug.cc
index 5b8fb1231db0cb1d0e8e82da85e4b9ca83c34b6a..b6884b6795e4bb355ed169f343d7dba1e860d007 100644
--- a/src/runtime/runtime-debug.cc
+++ b/src/runtime/runtime-debug.cc
@@ -1182,7 +1182,7 @@ RUNTIME_FUNCTION(Runtime_PrepareStep) {
   // Get the step action and check validity.
   StepAction step_action = static_cast<StepAction>(NumberToInt32(args[1]));
   if (step_action != StepIn && step_action != StepNext &&
-      step_action != StepOut && step_action != StepFrame) {
+      step_action != StepOut) {
     return isolate->Throw(isolate->heap()->illegal_argument_string());
   }
 
@@ -1194,19 +1194,6 @@ RUNTIME_FUNCTION(Runtime_PrepareStep) {
   return isolate->heap()->undefined_value();
 }
 
-RUNTIME_FUNCTION(Runtime_PrepareStepFrame) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(0, args.length());
-  CHECK(isolate->debug()->CheckExecutionState());
-
-  // Clear all current stepping setup.
-  isolate->debug()->ClearStepping();
-
-  // Prepare step.
-  isolate->debug()->PrepareStep(StepFrame);
-  return isolate->heap()->undefined_value();
-}
-
 // Clear all stepping set by PrepareStep.
 RUNTIME_FUNCTION(Runtime_ClearStepping) {
   HandleScope scope(isolate);